Silicon carbide (SiC) is expected as a material for next generation semiconductor devices. Compared to silicon, silicon carbide has superior physical properties such as a band gap of about 3 times, a breakdown electric field strength of about 10 times, and a thermal conductivity of about 3 times. By utilizing this physical property, it is possible to realize a semiconductor device capable of operating with low loss and at high temperature.
When a short-circuit occurs in the load while a MOSFET (Metal Oxide Semiconductor Field Effect Transistor) using silicon carbide is turned on, a high voltage is applied between the drain and source of the MOSFET. When a high voltage is applied between the drain and source, breakdown of the MOSFET occurs. Breakdown of MOSFET is thought to be due to heat generation caused by large current flow.
In order to avoid breakdown of the MOSFET, it is required to lengthen the time from the short-circuit of the load to the breakdown of the MOSFET. In other words, it is required to improve short-circuit withstand capability.